US Department of Energy to fund Carbon Capture Project

Southern California Gas Co. (SoCalGas) and the Pacific Northwest National Laboratory (PNNL) have announced the US Department of Energy (DOE) has awarded US$300 000 in funding to a project that would advance the development of a process called Integrated CO2 Capture and Conversion to Methanol (ICCCM). Carbon capture and utilisation (CCU) projects are an important component in helping California achieve its climate goal of having a ‘net zero’ economy by 2045. CCU projects harness carbon before it can be emitted into the atmosphere. The carbon is then typically used to make chemicals that become resins and plastic materials.

The DOE funding for this project will be used to design, fabricate and demonstrate a modular ICCCM prototype for the combined capture and conversion of CO2 into methanol. As part of the research, the commercial viability of the prototype will also be assessed. The unit will be designed for installation at an industrial CO2 source, such as an electric generation or anaerobic digestion facility.

SoCalGas is committed to helping California achieve its ambitious climate goals. The utility has spent more than US$10 million on the research and development of low or zero carbon technologies in the last three years.

"As we look for ways to reduce greenhouse gas emissions in support of the state's climate goals, we will need to develop cost-effective technologies that can capture and use CO2 to prevent it from reaching the atmosphere," said Yuri Freedman, Senior Director of Business Development for SoCalGas. "The goal of this project is to determine whether ICCCM technology can be a cost-effective way to reduce emissions and it is our hope the results will show that it is."

"At PNNL, we specialise in carbon capture and catalysis research and are thrilled to be collaborating with SoCalGas on developing a new and innovative capture and conversion technology and deploying this technology into the field," said Dr. David Heldebrant, who is co-leading this project and is PNNL chief scientist for separations materials "Our role in this project is to design a continuous catalytic process that can take waste CO2 and repurpose it as a low carbon fuel or chemical feedstock with a large market size, such as a methanol."

What is ICCCM

ICCM uses flue gas from a power generation or heating source, cools the gas and then runs it through a CO2 absorber. In this absorber, CO2 is efficiently captured by PNNL's proprietary ‘Carbon Dioxide Binding Organic Liquids’" solvent. The solvent is then pressurised, heated and passed through to the main reactor, along with hydrogen, for methanol production. The reactor produces a methanol and water mixture which is then pumped into a distillation column designed to produce methanol at a purity of 99.6%. The excess hydrogen and solvent from the reactor are recycled back to the CO2 absorber.

The ICCCM technology is unique because hydrogen is used as an indirect energy source to drive the carbon capture process rather than steam or electricity. Also, by using the ICCCM solvent to directly convert CO2 to methanol, no mechanical compression of the CO2 is required. Typically, compressing CO2 is energy-intensive, so reducing the need for additional energy inputs makes the ICCCM technology a potentially viable solution to capture and convert CO2 from landfill gases, wastewater treatment gases and manure off-gas.

California has set an ambitious goal of having a net zero economy by 2045, meaning the amount of carbon emitted into the atmosphere is no more than the amount of carbon taken out. While carbon neutrality is a good first step, research continues into finding ways to be carbon negative, i.e. remove more carbon from the atmosphere than is produced. One potential way to do this is to use green hydrogen created from renewable energy such as wind or solar is used in carbon capture and utilisation.

Why methanol?

Methanol is used in a number of ways, from a feedstock in the chemical industry to a component in fuel blends like marine fuel and bio-diesel. For example, methanol is used to produce acetic acid and formaldehyde, which in turn are used in products like adhesives, foams, plywood subfloors, solvents and windshield washer fluid. Today, methanol is primarily made from syngas created from natural gas and other fossil fuels and current methanol production leads to greenhouse gas emissions. Using CO2 capture technology to create methanol can serve two purposes – first, it prevents carbon emissions which are produced from conventional syngas-to-methanol technologies from reaching the atmosphere, and second, COs utilisation helps offset some of the costs incurred with carbon capture.

Over the next two years, this project will evaluate the compatibility of certain catalysts and solvents, design and build the reactor and test the unit. The later stages of this research will also assess the viability of producing polycarbonates.